From Politico.com

Sen. John McCain (R-Ariz.) plans to celebrate his 72nd birthday on Aug. 29 by naming his running mate at a huge rally in the battleground state of Ohio, Republican sources said.

That’s a week from Friday, and the day after his rival, Sen. Barack Obama of Illinois, accepts the Democratic nomination at a 70,000-person spectacular in a Denver stadium.

The campaign has begun building a crowd of 10,000 for Dayton, Ohio, according to an organizer. McCain is scheduled to appear with his running mate at a large-scale event in Pennsylvania shortly thereafter.

Senior Republicans are in the dark about who he’ll name, although they say former Massachusetts Gov. Mitt Romney and Minnesota Gov. Tim Pawlenty are prime contenders after a trial balloon by McCain gave him very negative feedback about the idea of picking an abortion-rights running mate such as Tom Ridge, the former governor of Pennsylvania and the first secretary of homeland security.

Sources close to McCain say he has wrestled with the choice, torn between a high-stakes, high-reward pick like Ridge or Connecticut Sen. Joseph I. Lieberman — the Democratic vice presidential nominee in 2000 — or a safer and more conventional selection such as Romney or Pawlenty.

Friends say he has yet to make a final decision, and is not expected to do so until after Sen. Barack Obama announces his choice.

McCain friends emphasized that he talks about the decision with almost no one, and could even change the announcement plans and go sooner.

“McCain views this as the one decision that he has total, utter, nonnegotiable control over,” one campaign official said.

The announcement strategy — provided McCain doesn’t change it — calls for naming the pick early Friday morning to try to suppress Obama’s bounce coming out of his convention.

“You’re going to own the weekend,” a McCain official said.

The Republican convention begins the following Monday — Labor Day — in St. Paul, Minn.

McCain advisers say they don’t think it would make sense to name the vice presidential designee earlier because the impact would get diluted by Obama’s selection. And because the GOP convention is second, they have the advantage of knowing the opposition ticket before showing their own cards.

“You can fire the bullet once,” said one key Republican. “You want the most meaningful target.”

Alex M. Triantafilou, chairman of the Hamilton County (Ohio) Republican Party, said in an exuberant post on his blog this weekend: “Sen. McCain is expected to host a rally on August 29 in Dayton and is looking for a BIG venue and for a BIG crowd. He'll get it. This is not yet public. I guess I just made it so.”

The post has been removed without explanation.

PolitickerOH.com reported Monday morning that the event will be at the 10,000-seat Ervin J. Nutter Center, a sports and entertainment complex at Wright State University.